国防科学技术大学 光电科学与工程学院, 长沙 410073
采用2.5维粒子模拟软件对改进型低阻类膜片加载同轴渡越时间振荡器进行了研究。研究结果表明:提取腔工作于类π模场时,具有较高的束波互作用效率;引入渐变型输出波导,提高了提取腔内微波向外耦合输出的能力;通过加载感性支撑杆,一方面对金属膜片起支撑固定作用,另一方面可以及时将膜片上的感应电荷导流至接地外筒、从而降低间隙附近的空间电荷效应,以增加可提取的束动能。经优化设计,该结构在二极管电压为530 kV,二极管电流为12.9 kA、外加导引磁场为0.5 T的条件下,输出微波功率2.74 GW,微波频率7.76 GHz,束波功率转换效率达40%。
类膜片结构 渐变型输出波导 感性支撑杆 粒子模拟 washer-like structure tapered output waveguide inductive metal rods particle-in-cell simulation 强激光与粒子束
2013, 25(11): 2943
Author Affiliations
Abstract
State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
Square microcavity laser with an output waveguide is proposed and analyzed by the finite-difference time-domain (FDTD) technique. For a square resonator with refractive index of 3.2, side length of 4 microns, and output waveguide of 0.4-micron width, we have got the quality factors (Q factors) of 6.7*10^(2) and 7.3*10^(3) for the fundamental and first-order transverse magnetic (TM) mode near the wavelength of 1.5 microns, respectively. The simulated intensity distribution for the first-order TM mode shows that the coupling efficiency in the waveguide reaches 53%. The numerical simulation shows that the first-order transverse modes have fairly high Q factor and high coupling efficiency to the output waveguide. Therefore the square resonator with an output waveguide is a promising candidate to realize single-mode directional emission microcavity lasers.
时域有限差分法 正方形谐振腔 输出波导 定向发射 140.4780 Optical resonators 140.3410 Laser resonators 140.3570 Lasers, single-mode 230.3990 Micro-optical devices Chinese Optics Letters
2007, 5(8): 463